Silyl-Functionalized Electrolyte Additives and Their Reactivity toward Lewis Bases in Li-Ion Cells

Silyl groups are included in a wide range of electrolyte additives to enhance the performance state-of-the-art Li-ion batteries. A recognized representative thereof is tris-(trimethylsilyl)phosphate (TMSPa) which, along with similarly structured phosphite, has been at center numerous studies. Even though silyl group already widely reported be specifically reactive towards fluorides, herein, reactivity several Lewis bases typically found cells postulated and investigated aim establish more simplified generally applicable reaction mechanism thereof. Both gaseous soluble reactants products monitored by combining nuclear magnetic resonance injection cell-coupled mass spectrometry. Experimental observations supported computational models. The results clearly demonstrate that react water, hydroxide, methoxide thereby detach stepwise fashion from central phosphate TMSPa. Intermolecular interaction between TMSPa likely facilitates dissolution lowers free energy reaction. well known trigger side reactions involving both electrode electrolyte. By effectively scavenging these, can explained lower cell impedance prolong lifetime modern